1. Field of the Invention
The present invention relates, in general, to a computer system and, more particularly, to a computer system wherein a user can selectively output audio signals within a frequency band desired by him.
2. Description of the Related Art
These days, a computer system can process information composed of a mixture of a variety of medias, such as voices, characters, graphics, images, etc., in addition to word-processing or computing. In particular, a number of computer systems are equipped with sound cards outputting sounds. For example, the sound card converts sound data from the CD-ROM into audio data and outputs the audio data through the speaker.
Among the computer systems, to cope with the users' requests to make the main system of a notebook computer slimmer, a docking station to be connected to the main system has been widely used. Generally, a docking station is a hardware frame and a set of electrical connection interfaces that enable a notebook computer to effectively serve as a desktop computer. The docking station interfaces typically allow the notebook computer to communicate with a local printer, larger storage or backup drives, and possibly other devices that are not usually taken along with a notebook computer.
Recently, as the computer users have focused their interests in multimedia, there has been disclosed a docking station expanding sound output functions. An audio amplifier is installed within the docking station, and a low-pitched sound speaker is attached to the docking station, whereby the user can hear low-pitched sounds. However, in the conventional notebook computer system, the user can only hear a mean sound at the main system of the conventional notebook computer.
Next, an example process of outputting an audio sound from the notebook computer on which the docking station is mounted will be described in brief. For example, in the notebook computer, the sound data from a CD-ROM is converted into analog audio signals through a DAC (digital-to-analog converter) chip integrated within the sound card. The converted audio signals are amplified through an audio amplifier and then output to the speaker. Here, the speaker installed in the main system of the notebook computer is constructed to pass main frequency ingredients of the audio signals, thereby allowing the mean sound to be output at the main system.
Further, if the docking station is connected, audio signals can be transmitted to the docking station through a docking connector, and the transmitted audio signals are amplified through the audio amplifier of the docking station and output to the speaker installed in the docking station. Since a low-pitched sound speaker having no limitation in size and being large in diameter can be installed in the docking station, sounds of low frequency have generally been output at the docking station. However, this computer system configuration still has a limitation of outputting sounds of high frequency, even though the sound functions are supposed to have been expanded by the docking station. Further, the computer system does not allow selection of audio signal output according to a frequency band and/or controlling audio signal output location in the computer system.